Basic concepts of optical assembly and adjustment
Writer： admin Time：2020-01-15 16:53 Browse：℃
The assembly requirements of optical instruments are different due to their different structures, USES and environments. For the observation instrument, it should mainly meet the requirements of optical system performance and image quality. For measuring and aiming instruments, the quality and accuracy of the mechanism shall also be ensured. The binocular instrument must ensure the realization of its stereoscopic effect; Systems containing prisms and mirrors shall eliminate imaging position errors caused by their position errors. For photographic instruments and photoelectric instruments should also eliminate non-designed harmful stray light beam, there are strict requirements to prevent stray light. Optical instruments used in the field are required to be able to adapt to the environment of field operations, that is, to require fastness, tightness and stability.
I. assembly features of optical instruments
Optical instruments are instruments that use optical imaging principles for observation, measurement, recording and analysis. Compared with other mechanical and electronic instruments, their assembly has the following characteristics:
(1) when the optical element is connected with the mechanical part, it shall have sufficient firmness and at the same time minimize the internal stress caused by the deformation of the optical element due to the connection, so as to ensure the imaging quality of the optical element.
(2) the surface of parts is required to be very clean, especially the surface of optical parts. If the surface of the optical part in the system is not clean, it will affect the transparency of the optical system and affect the observation effect of the product. The presence of dirt on or near the image surface can interfere with the observation of the object and sometimes create illusions. Also requires the cleaning of the inner surface of the product, otherwise when the product is subjected to vibration and impact, the dirt on the inner surface of the product (dust, fiber, paint particles, metal particles, etc.) fall on the surface of the optical parts, will also produce the above effects.
(3) different assembly * methods are adopted in the assembly process to eliminate the overall out-of-tolerance of accuracy caused by the economy of parts processing. These assembly methods are specified in the product design and are listed in the technical requirements section of the product assembly drawing. These methods are usually called compensation methods.
(4) different types of optical instruments shall meet their respective operational requirements. Some work indoors, in a fixed place, and at room or constant temperature; Some are used in the field, the working place is not fixed, by the use of the environment, such as vibration, impact, sun, rain, and sand, dust and so on. Therefore, strict requirements are put forward for the fastness, tightness and stability of such products.
For this reason, it is not allowed to leave damp gas and other harmful gas in the cylinder during the assembly process. Mechanical parts in contact with optical parts should be degreased well; The dustproof grease, lubricating grease and sealing material used in the mirror tube must ensure the quality. Otherwise, it will cause mold and fog on the surface of the optical element as time goes by.
Ii. Assembly and adjustment of optical instruments
The task of assembly and adjustment is to assemble each part into the product at the lowest cost and the highest speed and to meet the technical requirements on the assembly drawing and the general acceptance technical conditions.
The so-called "adjustment" is to use the compensation method to install the qualified parts and components of the product to the position required by the design. It can be realized by using the adjustment mechanism stipulated in advance in the product design, and can also be used to repair or replace the specified parts to meet the expected technical requirements. This role in the adjustment process includes the meaning of inspection, correction and adjustment.
The term "adjustment" also means the correction and adjustment during the use of the product.
The term "test" means the test of a product's performance under a service condition directly or in a device simulating that service condition.
In a word, the assembly process of products generally includes the following aspects:
Assembly shall connect all qualified parts and components according to the relationship and requirements shown in the product drawings.
Inspection according to the given technical requirements, take the corresponding inspection methods and means to observe and measure, find out the product should eliminate the error.
Adjust according to the technical requirements on the product assembly drawing and adopt the corresponding compensation method to reduce the inspected error to the required range.
Fastening fixed adjustment results.
According to the requirements of the service conditions, necessary tests (such as vibration, sealing, high and low temperature, etc.) are carried out to assess the design and assembly quality of the products.